Light bulb



FIG. 1 is an isometric view of a light bulb, showing an embodiment ofthe new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

Subject matter shown in broken lines is environmental and forms no partof the claimed design.

CLAIM The ornamental design for the light bulb, as shown and described.